This invention relates in general to protection of internal combustion engines to reduce overheating and subsequent engine failure, and more particularly to protection of small engines used in high-debris environments such as in roof-removing machines.
U.S. Pat. No. 5,167,209 illustrates such a roof-removing machine. U.S. Pat. Nos. 2,445,965; 2,601,907; 2,736,301; 2,848,987; 2,972,340; 3,147,814; 3,183,899; 3,252,449; 3,744,468; 3,994,067; 4,134,370; 4,261,302; 4,438,733; 4,446,681; 4,770,262; 4,946,482; 4,970,933; 4,998,510; and 5,167,209 illustrate various filtering arrangements for air-cooled engines.
When operated in dirty environments, such as in roof removing machines, air-cooled engines often overheat because debris drawn into the air cooling intake coats the fan blades and cooling fins, reducing heat dissipation and clogging the air intake. The reduced efficiency of the cooling system in turn causes the engine to overheat, creating a high potential for engine failure. Additionally, debris-ridden air is drawn into the carburetor air inlet area, restricting air flow and preventing proper functioning of the engine. Although various screens and filters have been provided for engines, adequate filtration is not available for engines of this type used in high-debris environments.